Linux Kernel Netfs Component Denial-of-Service Vulnerability

A denial-of-service vulnerability has been identified in the Linux kernel's netfs component. When the configuration option 'CONFIG_NETFS_SUPPORTS' is enabled and 'CONFIG_PROC_FS' is disabled, the system can crash. This issue arises because the netfs initialization process attempts to create a directory in the proc filesystem without checking if procfs is enabled, leading to a kernel crash.

Impact

Exploitation of this vulnerability causes a kernel crash, disrupting system operations and potentially leading to a denial-of-service condition.

Reproduction

To reproduce this vulnerability, configure the Linux kernel with 'CONFIG_NETFS_SUPPORTS' enabled and 'CONFIG_PROC_FS' disabled. When the system is booted with this configuration, it will crash shortly after startup, displaying a kernel bug message and a stack trace indicating the source of the error in the netfs component.

Remediation

The vulnerability has been addressed in the Linux kernel by modifying the netfs initialization process to only create the '/proc/fs/netfs' directory when 'CONFIG_PROC_FS' is enabled.